Hybrid electric vehicle, drive control method and device of the same

ABSTRACT

The present disclosure provides a hybrid electric vehicle, a drive control method and a drive control device of a hybrid electric vehicle. The drive control method includes: obtaining a current gear position of the hybrid electric vehicle and a current electric charge level of a power battery; obtaining a slope of a road on which the hybrid electric vehicle is driving, if the current gear position of the hybrid electric vehicle and the current electric charge level of the power battery meet a preset requirement; and causing a working state of an engine and/or a motor of the hybrid electric vehicle according to the slope of the road on which the hybrid electric vehicle is driving.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority and benefits of Chinese PatentApplication No. 201510133521.9, filed with State Intellectual PropertyOffice, P. R. C. on Mar. 25, 2015, the entire content of whichapplication is incorporated herein by reference.

The present application is related to U.S. patent application Ser. No.15/078,942 entitled “HYBRID ELECTRIC VEHICLE, DRIVE CONTROL METHOD ANDDEVICE OF THE SAME” filed Mar. 23, 2016, U.S. patent application Ser.No. 15/078,947 entitled “HYBRID ELECTRIC VEHICLE, DRIVE CONTROL METHODAND DEVICE OF THE SAME” filed Mar. 23, 2016, U.S. patent applicationSer. No. 15/078,951 entitled “HYBRID ELECTRIC VEHICLE, DRIVE CONTROLMETHOD AND DEVICE OF THE SAME” filed March 23, U.S. patent applicationSer. No. 15/078,953 entitled “HYBRID ELECTRIC VEHICLE, DRIVE CONTROLMETHOD AND DEVICE OF THE SAME” filed Mar. 23, 2016, and U.S. patentapplication Ser. No. ______ entitled “HYBRID ELECTRIC VEHICLE, DRIVECONTROL METHOD AND DEVICE OF THE SAME” filed Mar. 24, 2016 (AttorneyDocket No. 100758-5070-US), all of which are incorporated by referencein their entirety.

TECHNICAL FIELD

The present disclosure relates to vehicle technology field, moreparticularly to a hybrid electric vehicle, a drive control method and adrive control device of the hybrid electric vehicle.

BACKGROUND

A traditional fuel vehicle is usually equipped with an additionalautomatic start-stop subsystem for realizing taxiing start-stop controlon the vehicle, and thus fuel waste and air pollution caused by engineidling are reduced. There have been following forms of start-stopsystems in vehicles.

1. Separating starter/generator start-stop system

In such a system, the starter and the generator are designed separately,in which the starter is used to provide power for starting an engine,and the generator is used to provide electric energy for the starter.This system includes a high enhanced starter, an enhanced battery(usually an AGM battery), a controllable generator, an engine ECU(Electronic Control Unit) with integrated start-stop coordinationprogram, and a sensor, etc. In this system, the engine is started by thestarter separately.

2. Integrated Starter/Generator Start-Stop System

The integrated start/generator is a synchronous machine actuated by asingle teeth stator and a rotor in a permanent magnet, and a drivingunit may be integrated into a hybrid power transmission system. Withthis system, the engine may be started by revise driving from the motor.

3. i-Start System

An electric control device is integrated in the generator. The enginestops when the vehicle stops at a red light, and automatically starts assoon as engaging a gear or releasing a brake pedal.

When the vehicle is driven on heavy-traffic roads, the engine will bestarted frequently, that is a huge test for both a spark plug and abattery. Although the start-stop systems described-above are intelligentenough, a service life of the engine will be shorten as an abrasion onthe engine, and a vibration and a noise are inevitable as frequentstart-stop, which severely reduces the comfort. In addition, theautomatic start-stop system may work only in such conditions that avehicle speed is 0, a rotating speed of the engine is lower than aprescribed target speed, the refrigerant is in a required range, thevacuum braking meets a required condition, an air conditioner isadjusted suitably, the braking pedal is depressed at a certain gearposition (like N or P), and an electric charge level of the powerbattery meets a next start. Since the start-stop system is limited onmany aspects, system units are required to have a high reliability anddurability. Moreover, the special start-stop system increases the costof the vehicle.

SUMMARY

Embodiments of the present disclosure seek to solve at least one of theproblems existing in the related art to at least some extent.

According to embodiments of a first aspect of the present disclosure, adrive control method of a hybrid electric vehicle is provided. Themethod includes: obtaining a current gear position of the hybridelectric vehicle and a current electric charge level of a power battery;obtaining a slope of a road on which the hybrid electric vehicle isdriving, if the current gear position of the hybrid electric vehicle andthe current electric charge level of the power battery meet a presetrequirement; and causing a working state of an engine and/or a motor ofthe hybrid electric vehicle according to the slope of the road on whichthe hybrid electric vehicle is driving.

With the drive control method of the hybrid electric vehicle accordingto embodiments of the present disclosure, when the current gear positionof the hybrid electric vehicle and the current electric charge level ofthe power battery meet a preset requirement, the hybrid electric vehicleis configured to enter a small load stop mode or a small load stall modeaccording to the slope of the road on which the hybrid electric vehicleis driving. In this way, a driving distance for the vehicle may beincreased, an economy performance may be improved, and fuel consumptionand emission may be reduced, without increasing a working frequency ofthe starter, thus ensuring a working life of components. In addition, ifthe vehicle has an accelerator-releasing energy feedback function,wasted kinetic energy may be converted to electric energy by a motorthrough the energy feedback and stored in a power battery, thusincreasing energy recovery. Moreover, for the hybrid electric vehicles,problems of bad ride comfort and bad power performance caused byfrequent start-stop of the engine may be solved effectively.

According to embodiments of a second aspect of the present disclosure, adrive control device of a hybrid electric vehicle is provided. Thedevice includes: a first obtaining module, configured to obtain acurrent gear position of the hybrid electric vehicle and a currentelectric charge level of a power battery; a second obtaining module,configured to obtain a slope of a road on which the hybrid electricvehicle is driving, if the current gear position of the hybrid electricvehicle and the current electric charge level of the power battery meeta preset requirement; and a first control module, configured to controla working state of an engine and/or a motor of the hybrid electricvehicle according to the slope of the road on which the hybrid electricvehicle is driving.

With the drive control device of the hybrid electric vehicle accordingto embodiments of the present disclosure, when the current gear positionof the hybrid electric vehicle and the current electric charge level ofthe power battery meet a preset requirement, the hybrid electric vehicleis configured to enter a small load stop mode or a small load stall modeaccording to the slope of the road on which the hybrid electric vehicleis driving. In this way, a driving distance for the vehicle may beincreased, an economy performance may be improved, and fuel consumptionand emission may be reduced, without increasing a working frequency ofthe starter, thus ensuring a working life of components. In addition, ifthe vehicle has an accelerator-releasing energy feedback function,wasted kinetic energy may be converted to electric energy by a motorthrough the energy feedback and stored in a power battery, thusincreasing energy recovery. Moreover, for the hybrid electric vehicles,problems of bad ride comfort and bad power performance caused byfrequent start-stop of the engine may be solved effectively.

According to embodiments of a third aspect of the present disclosure, ahybrid electric vehicle is provided. The hybrid electric vehicleincludes the drive control device mentioned in the above embodiments ofthe second aspect of the present disclosure.

With the hybrid electric vehicle according to embodiments of the presentdisclosure, when the current gear position of the hybrid electricvehicle and the current electric charge level of the power battery meeta preset requirement, the hybrid electric vehicle is configured to entera small load stop mode or a small load stall mode according to the slopeof the road on which the hybrid electric vehicle is driving. In thisway, a driving distance for the vehicle may be increased, an economyperformance may be improved, and fuel consumption and emission may bereduced, without increasing a working frequency of the starter, thusensuring a working life of components. In addition, if the vehicle hasan accelerator-releasing energy feedback function, wasted kinetic energymay be converted to electric energy by a motor through the energyfeedback and stored in a power battery, thus increasing energy recovery.Moreover, for the hybrid electric vehicles, problems of bad ride comfortand bad power performance caused by frequent start-stop of the enginemay be solved effectively.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects and advantages of embodiments of the presentdisclosure will become apparent and more readily appreciated from thefollowing descriptions made with reference to the accompanying drawings,in which:

FIG. 1 is a flow chart of a drive control method of a hybrid electricvehicle according to an embodiment of the present disclosure;

FIG. 2 is a flow chart of determining whether a hybrid electric vehicleis within a taxiing start-stop interval or a speech start-stop intervalaccording to an embodiment of the present disclosure;

FIG. 3 is a flow chart of causing a hybrid electric vehicle to enter asmall load stop mode or a small load stall mode according to anembodiment of the present disclosure;

FIG. 4 is a schematic diagram of energy transfer in a drive controlprocess of a hybrid electric vehicle according to an embodiment of thepresent disclosure;

FIG. 5 is a schematic diagram of control information interaction in adrive control process of a hybrid electric vehicle according to anembodiment of the present disclosure;

FIG. 6 is a flow chart of a drive control method of a hybrid electricvehicle according to an example embodiment of the present disclosure;

FIG. 7 is a block diagram of a drive control device of a hybrid electricvehicle according to an embodiment of the present disclosure;

FIG. 8 is a block diagram of a drive control device of a hybrid electricvehicle according to another embodiment of the present disclosure; and

FIG. 9 is a block diagram of a drive control device of a hybrid electricvehicle according to yet another example embodiment of the presentdisclosure.

DETAILED DESCRIPTION

Example embodiments will be described in detail herein, and examplesthereof are illustrated in accompanying drawings. Throughout figuresreferred by the following description, the same reference number indifferent figures indicates the same or similar elements unlessotherwise stated. Implementations described in the following exemplaryembodiments do not represent all the implementations consistent with thepresent disclosure. Instead, they are only examples of the device andmethod consistent with some aspects of the present disclosure.

A drive control method and device of a hybrid electric vehicle accordingto embodiments of the present disclosure will be described withreference to drawings.

FIG. 1 is a flow chart of a drive control method of a hybrid electricvehicle according to an embodiment of the present disclosure.

As shown in FIG. 1, the drive control method according to someembodiments of the present disclosure includes following steps.

In step S101, a current gear position of the hybrid electric vehicle anda current electric charge level of a power battery are obtained.

The current gear position may be obtained by a gearbox system of thehybrid electric vehicle through obtaining a gear signal. The currentelectric charge level of the power battery may be obtained by a BMS(Battery Management System) in the hybrid electric vehicle.

Specifically, the current gear position of the hybrid electric vehicleand the current electric charge level of the power battery may beobtained via communication between an internal communication network ofthe hybrid electric vehicle, e.g. CAN (Controller Area Network) and thegearbox system, the BMS.

In step S102, a slope of a road on which the hybrid electric vehicle isdriving is obtained, if the current gear position of the hybrid electricvehicle and the current electric charge level of the power battery meetthe preset requirement.

Specifically, if the current gear position of the hybrid electricvehicle and the current electric charge level of the power battery meeta requirement for entering a taxiing start-stop interval, it isdetermined that the current gear position and the current electriccharge level meet the preset requirement.

In embodiments of the present disclosure, the drive control method maybe performed only when the gear position of the vehicle is atD-position.

When the power battery of the hybrid electric vehicle could offerelectric energy, a motor can work, and then the vehicle can have thetaxiing start-stop function. Thus, the taxiing start-stop control isperformed when the electric charge level of the power battery issufficient.

Since a motor has a limited power output, it is difficult for the motoras an alone driving source to satisfy the power requirement of thevehicle, especially when the vehicle is climbing a sizable uphill slope.Thus, an engine is required to output power when the vehicle is climbinga slope. However, when the vehicle is driving downhill, the drivingresistance may be completely overcome by gravity inertia, and thus therequired torque is small. In this case, the engine may be configured tostop, a clutch may be released totally, and only the motor may be usedto output power. On one hand, the fuel needed during the engine idlingis saved, and on the other hand, if the hybrid electric vehicle has theaccelerator-releasing energy feedback function, an energy feedback bythe motor may be increased, since the clutch is completely released, anda drag force from the engine disappears.

Alternatively, a current operating mode of the hybrid electric vehicleand a discharge power of the power battery may also be obtained, and itmay be determined whether the hybrid electric vehicle is within thetaxiing start-stop interval according to the current gear position andthe current operating mode of the hybrid electric vehicle, the currentelectric charge level and the discharge power of the power battery.

Specifically, the voltage and the current of the power battery may beobtained via data collectors in the BMS in real time, and then thecurrent electric charge level and the allowable discharge power of thepower battery may be computed. When the vehicle is at a low temperatureor when the vehicle has a fault, the power battery has a risk of overdischarge and over-low voltage. Thus, in order to protect the powerbattery from damage and prolong a use life of the power battery, thedischarge power should be limited when the vehicle is at the lowtemperature or when the vehicle has a fault. At this time, the vehiclecannot output power normally.

A motor controller may determine a mode of the hybrid electric vehicleaccording to a mode switch signal, and then choose different drivingstrategies. Generally, the hybrid electric vehicle includes two workingmodes (electric mode and hybrid mode, namely EV mode and HEV mode) andtwo driving modes (Economy mode and Sport mode, namely ECO mode andSport mode). Therefore, the hybrid electric vehicle may have four kindsof operating modes, such as EV-ECO mode, EV-Sport mode, HEV-ECO mode andHEV-Sport mode. In the EV mode, the vehicle is in a pure electric energyconsumption mode and the motor outputs power separately; in the HEVmode, the vehicle is in a hybrid energy consumption mode, and a ratio ofpower output by the motor to power output by the engine is determinedaccording to a preset strategy. In the ECO mode, the power output fromthe motor and the engine is limited since the economy is a primarycontrol target; in the Sport mode, the power output from the motor andthe engine is not limited since the power performance is the primarycontrol target, especially, in the hybrid sport mode (HEV-Sport mode),the engine remains running.

FIG. 2 is a flow chart of determining whether a hybrid electric vehicleis within a taxiing start-stop interval or a speech start-stop intervalaccording to an embodiment of the present disclosure. As shown in FIG.2, following steps are performed.

In step S201, it is determined whether the current electric charge levelof the power battery is greater than a first electric charge levelthreshold, and whether the discharge power of the power battery isgreater than a first power threshold, if the current gear position is atD-position, and the current operating mode is the hybrid economy mode(HEV-ECO mode).

The first electric charge level threshold and the first power thresholdmay be determined according to a minimum electric charge level and aminimum discharge power at which the power battery may supply powernormally. When the electric charge level of the power battery is lessthan or equal to the first electric charge level threshold or when thedischarge power of the power battery is less than or equal to the firstpower threshold, the power battery may take the risk of over dischargingand low voltage alarm. Therefore, in order to protect the power batteryfrom damage and ensure the working life of the power battery, the firstelectric charge level threshold and the first power threshold should beset.

In step S202, if the current electric charge level of the power batteryis greater than the first electric charge level threshold, and thedischarge power of the power battery is greater than the first powerthreshold, it is further determined whether the current electric chargelevel is greater than or equal to a second electric charge levelthreshold, and whether a difference between the current electric chargelevel and a target electric charge level of the power battery is lessthan or equal to a preset value.

The target electric charge level is an electric charge level which thepower battery finally has when charging or discharging under the HEVmode.

Therefore, if the difference between the current electric charge leveland the target electric charge level of the power battery is less thanor equal to the preset value, the current electric charge level of thepower battery is relatively high and has a smaller difference with thetarget electric charge level, and the power battery is in a balancestate. In this case, the power battery may not only meet a currentdriving requirement, but also is in a stable discharge state, and thusover discharging may be avoided effectively when the hybrid electricvehicle enters a small load control function, thereby protecting thepower battery, prolonging the working life of the power battery, andkeeping a better power performance and stability for the hybrid electricvehicle.

The small load control function refers to a drive control function usedwhen the electric charge level of the power battery is large enough(e.g. the electric charge level is larger than a second electricthreshold), the discharge power of the power battery is greater than thefirst power threshold, and the slope of the road satisfies followingconditions:

the road is ascent and the slope of the road is less than a first slopethreshold; or

the road is descent and the slope of the road is greater than or equalto a second slope threshold.

The second electric threshold is an electric charge level which maysatisfy the requirement of driving in a pure electric mode at a lowspeed, such that part of the electric charge level are reserved fordriving in a pure electric mode at a low speed when a taxiing start-stopcontrol is performed, thus keeping the better power performance andstability for the hybrid electric vehicle. The first electric thresholdand the second electric threshold may be set according to the drivinghabit of the user and the power consumption of the hybrid electricvehicle.

In step S203, if the current electric charge level is greater than orequal to the second electric charge level threshold, and the differencebetween the current electric charge level and the target electric chargelevel of the power battery is less than or equal to the preset value, itis determined that the hybrid electric vehicle is within the taxiingstart-stop interval.

In some embodiments of the present disclosure, step S204 is furtherincluded.

In step S204, if the current electric charge level is less than thesecond electric charge level threshold, or if the difference between thecurrent electric charge level and the target electric charge level ofthe power battery is greater than the preset value, it is determinedthat the hybrid electric vehicle is within a speed start-stop interval.

In the taxiing start-stop interval, the engine is configured to start,stop or stall, while the accelerator pedal is released. In the speedstart-stop interval, the engine is configured to start, stop or stall,while the accelerator pedal is depressed. The control strategy for thetaxiing start-stop interval needs to consider factors like the speed,the working state of the engine, and the accelerator push depth, whilethe control strategy for the speed start-stop interval needs to considerfactors like the speed and the slope of the road. In other words, in thespeed start-stop interval, the engine is configured according to thespeed and the slope of the road.

In some embodiments of the present disclosure, if the current gearposition of the hybrid electric vehicle and the current electric chargelevel of the power battery meet the preset requirement, a slope of aroad on which the hybrid electric vehicle is driving may be obtained viacomputing from a longitudinal acceleration of the vehicle, which isobtained by a longitudinal acceleration sensor in the hybrid electricvehicle.

Specifically, the slope of the road on which the hybrid electric vehicleis driving may be obtained via communication between an internalcommunication network of the hybrid electric vehicle, e.g. CAN(Controller Area Network) and the longitudinal acceleration sensor.

In step S103, a working state of an engine and/or a motor of the hybridelectric vehicle is configured according to the slope of the road onwhich the hybrid electric vehicle is driving.

Specifically, in some embodiments, it may be determined whether theslope of the road satisfies a preset condition. If the slope of the roadon which the hybrid electric vehicle is driving meets the presetcondition, the current speed of the hybrid electric vehicle may beobtained, and then the hybrid electric vehicle is configured to enter asmall load stop mode or a small load stall mode according to the currentspeed. The current speed of the hybrid electric vehicle may be obtainedfrom an ESC (Electrical Speed Controller) via the communication networkin the hybrid electric vehicle.

Specifically, if the road is ascent and the slope of the road is lessthan the first slope threshold, it is determined that the slope of theroad on which the hybrid electric vehicle is driving meets the presetcondition; if the road is descent and the slope of the road is greaterthan the second slope threshold, it is determined that the slope of theroad on which the hybrid electric vehicle is driving meets the presetcondition. If it is determined that the slope of the road on which thehybrid electric vehicle is driving doesn't meet the preset condition,for example, if the road is ascent and the slope of the road is greaterthan or equal to the first slope threshold, then the engine may bereleased from start-stop control, or if the road is descent and theslope of the road is less than the second slope threshold, then theengine is configured to stop and the motor is configured to output powerseparately.

In some embodiments, as shown in FIG. 3, causing the hybrid electricvehicle to enter the small load stop mode or the small load stall modeincludes following steps.

In step S301, the engine is configured to stop and the engine isconfigured to output power separately, if the current speed is less thana third speed threshold.

In step 302, the hybrid electric vehicle is configured to enter thesmall load stop mode, if the current speed is greater than or equal to athird speed threshold and less than a fourth speed threshold.

Specifically, it is first determined whether the engine is in anoperating state.

If the engine is not in the operating state, it is further determinedwhether an accelerator push depth is greater than or equal to a firstaccelerator threshold; if the accelerator push depth is greater than orequal to the first accelerator threshold, the engine is configured tostart; and if the accelerator push depth is less than the firstaccelerator threshold, a state of the engine remains unchanged.

If the engine is in the operating state, it is further determinedwhether the accelerator push depth is less than a second acceleratorthreshold; if the accelerator push depth is less than the secondaccelerator threshold, the engine is configured to stop; if theaccelerator push depth is greater than or equal to the secondaccelerator threshold, the state of the engine remains unchanged.

The first accelerator threshold and the second accelerator threshold maybe set according to the driving habit of the user and the powerconsumption of the vehicle. The second accelerator threshold is lessthan the first accelerator threshold, thus avoiding a frequent enginestart-stop caused by unclear accelerator thresholds.

In step S303, the hybrid electric vehicle is configured to enter thesmall load stall mode, if the current speed is greater than or equal tothe fourth speed threshold and less than a fifth speed threshold.

Specifically, it is first determined whether the engine is in anoperating state.

If the engine is not in the operating state, it is further determinedwhether an accelerator push depth is greater than or equal to a firstaccelerator threshold; if the accelerator push depth is greater than orequal to the first accelerator threshold, the engine is configured tostart; and if the accelerator push depth is less than the firstaccelerator threshold, a state of the engine remains unchanged.

If the engine is in the operating state, it is further determinedwhether the accelerator push depth is less than a second acceleratorthreshold; if the accelerator push depth is less than the secondaccelerator threshold, the engine is configured to stall, a clutch iskept in a coupling state and fuel supply for the engine is cut off; ifthe accelerator push depth is greater than or equal to the secondaccelerator threshold, the state of the engine remains unchanged.

In step S304, the state of the engine remains unchanged if the currentspeed is greater than or equal to the fifth speed threshold.

In embodiments of the present disclosure, the fifth speed threshold isgreater than the fourth speed threshold, and the fourth speed thresholdis greater than the third speed threshold. And the third speedthreshold, the fourth speed threshold and the fifth speed threshold maybe set according to the driving habit of the user and the powerconsumption of the vehicle.

In embodiments of the present disclosure, the vehicle has theaccelerator-releasing energy feedback function, and during theaccelerator is released, the lost kinetic energy is converted toelectric energy via the energy feedback of the motor and stored in thepower battery. In this case, if the engine is stopped, the clutch isreleased totally and the drag force from the engine disappears, then theenergy feedback by the motor is increased.

With the drive control method according to embodiments of the presentdisclosure, the hybrid electric vehicle is configured to enter the smallload stall mode when the speed of the hybrid electric vehicle isrelatively higher, since in this case, the vehicle motion inertia islarge, and the drag force from the engine is relatively small, and thushas a little impact on the feedback charging of the power battery.Furthermore, the clutch keeps the coupling state, such that it does notrequire coupling the clutch again, thus reducing the friction loss ofthe clutch. Moreover, the hybrid electric vehicle is configured to enterthe small load stop mode when the speed of the hybrid electric vehicleis relatively lower, when the vehicle speed is lower, the clutch isconfigured to open so as to avoid influence on charging the powerbattery, since in this case, the vehicle motion inertia is small, andthe drag force from the engine is relatively large, which has a greatimpact on the feedback charging of the power battery.

When the hybrid electric vehicle enter the small load stop mode or thesmall load stall mode, after causing the engine (the engine isconfigured to start, stop or stall, or the state of the engine remainsunchanged), a timing is started in order to determine whether to enternext drive control. Then, after the state of the engine is changed, thestate of the engine may be changed again only after a preset time, thusto avoid frequent start-stop of the engine.

After determining that the hybrid electric vehicle is within the speedstart-stop interval, the speed start-stop control may be performedaccording to the slope of the road and the current speed. Specifically,if the road is ascent and the slope of the road is greater than or equalto a third slope threshold, the engine is started; if the road isdescent and the slope of the road is greater than or equal to a fourthslope threshold, the engine is configured to stop, i.e., the fuel supplyfor the engine is cut off and the clutch is configured to be open (atthis time, the engine stops running), and the motor is configured tooutput power separately; if the road is ascent and the slope of the roadis less than the third slope threshold, and the current speed is greaterthan a first speed threshold, the engine is started; if the road isdescent and the slope less than the fourth slope threshold, and thecurrent speed is greater than the first speed threshold, the engine isstarted. After starting the engine, the current speed of the hybridelectric vehicle is obtained, and when the current speed of the hybridelectric vehicle is less than a second speed threshold, the engine isconfigured to stop, and the motor is configured to output powerseparately, and if the current speed of the hybrid electric vehicle isgreater than or equal to a second speed threshold, then step S101 isexecuted.

In embodiments of the present disclosure, stopping the engine refers toa state in which fuel supply for the engine is cut off and the clutch isreleased, causing the engine to stall refers to a state in which fuelsupply for the engine is cut off and the clutch is in a coupling state.

In the present disclosure, the first slope threshold, the second slopethreshold, the third slope threshold and the fourth slope threshold maybe set according to the driving habit of the user and the powerconsumption of the hybrid electric vehicle.

Specifically, FIG. 4 is a schematic diagram of energy transfer in adrive control process of the hybrid electric vehicle according to anembodiment of the present disclosure. As shown in FIG. 4, when the modeof the hybrid electric vehicle is the hybrid economy mode, the currentelectric charge level of the power battery (an electric charge level ofa high-voltage iron battery) is greater than the second electric chargelevel threshold, the discharge power is less than or equal to the firstpower threshold, and the slope of the road, the speed and theaccelerator push depth meet a condition for low-speed, small-throttleand low-power driving, the hybrid electric vehicle is driven by themotor separately, and the energy transfer is shown as route {circlearound (1)} in FIG. 4. If the discharge power of the hybrid electricvehicle is greater than the second power threshold (i.e. requiring alarge power driving), the engine is started to output power, and at thistime, the power is transferred to wheels via a DCT (Dual ClutchTransmission) gearbox and a reducer, which is shown as route {circlearound (2)} in FIG. 4. Moreover, when the current electric charge levelof the hybrid electric vehicle reduces to a certain electric chargelevel (less than or equal to the second electric charge levelthreshold), part of power of the engine is output to charge thehigh-voltage iron battery, the energy transfer of which is shown asroute {circle around (7)} in FIG. 4. In addition, when the vehicle istaxiing, the braking pedal is depressed during the driving, or when theengine automatically stalls and stops running during idling, the motorconverts the kinetic energy of the whole vehicle to the electric energyfor storing in the power battery, the energy transfer of which is shownas route {circle around (7)} in FIG. 4.

In embodiments of the present disclosure, the hybrid electric vehiclemay include the high-voltage iron battery used as the power battery anda low-voltage iron voltage used as the storage battery.

There are two ways for supplementing the electric charge level of thelow-voltage iron battery. The first one is driving the generator togenerate electricity when the engine start working, for charging thelow-voltage iron battery, the energy transfer of which is shown as route{circle around (5)} in FIG. 4, and the other one is transferring a highvoltage in the high-voltage iron battery to a low voltage by a DC-DCconverter, for charging the low-voltage iron battery, the energytransfer of which is shown as route {circle around (6)} in FIG. 4.

It can be seen that, in embodiments of the present disclosure, there aretwo ways for starting the engine. The first one is starting the enginedirectly by the starter, the energy transfer of which is shown as route□ in FIG. 4, and the other one is starting the engine via inertiaanti-drag force of the whole vehicle when the speed meets a requirement(i.e., the electric charge level of the power battery is large enough,such that the speed reaches the requirement of inertia anti-drag), theenergy transfer of which is shown as route □ in FIG. 4. Thus, if thespeed reaches the certain requirement, the starter does not need towork, such that a working frequency of the starter may not be increased,thus ensuring the working life of the components.

FIG. 5 is a schematic diagram of control information interaction in thedrive control process of the hybrid electric vehicle according to anembodiment of the present disclosure. As shown in FIG. 5, a speed signalis sent from an electronic stability controller (shown as ESC in FIG. 5)to a motor controller (shown as ECN in FIG. 5); a gear controller (shownas SCU in FIG. 5) is used to collect a gear signal and send the gearsignal to the ECN; a battery management system (shown as BMS is FIG. 5)is used to collect signals like current output power and currentelectric charge level and send collected signals to the ECN; the motorcontroller ECN is used to verify received signals like vehicle mode(such as EV/HEV/ECO/Sport mode) signal, accelerator signal or brakingpedal signal, send signals like a target torque of the engine, thevehicle mode, and start-stop identification of the engine to an enginecontrol module ECM, and send signals like the energy transfer state andthe vehicle mode to a combination instrument; the BMS performs thebattery monitoring and managing strategy; the ECM performs thestart-stop control strategy; and the combination instrument performs theenergy state and vehicle mode display strategy.

FIG. 6 is a flow chart of a drive control method of a hybrid electricvehicle according to an example embodiment of the present disclosure. Asshown in FIG. 6, the drive control method of the hybrid electric vehicleincludes following steps.

In step S601, it is determined whether the gear of the hybrid electricvehicle is at a preset position, if yes, step S602 is performed, and ifno, step S605 is performed.

The preset position may be D gear position.

In step S602, it is determined whether the hybrid electric vehicle is ina preset operating mode, if yes, step S603 is performed, and if no, stepS605 is performed.

The preset operating mode may be the hybrid economy mode.

In step S603, it is determined whether the current electric charge levelof the power battery is greater than the first electric charge levelthreshold, and whether the discharge power of the power battery isgreater than the first power threshold, if yes, step S604 is performed,and if no, step S605 is performed.

In step S604, it is determined whether the current electric charge levelof the hybrid electric vehicle is greater than or equal to the secondelectric charge level threshold, and whether the difference between thecurrent electric charge level and the target electric charge level ofthe power battery is less than or equal to the preset value, if yes,step S607 is performed, and if no, step S606 is performed.

In step S605, the hybrid electric vehicle quits from the enginestart-stop control.

In step S606, the hybrid electric vehicle enters the speed start-stopcontrol.

Specifically, if the road is ascent and the slope of the road is greaterthan or equal to a third slope threshold (p3), the engine is started,and the engine is configured to output power for the vehicle; if theroad is descent and the slope of the road is greater than or equal to afourth slope threshold (p4), the engine is configured to stop, and themotor is configured to output power separately; if the road is ascentand the slope of the road is less than the third slope threshold (p3),and the current speed is greater than a first speed threshold, theengine is started; if the road is descent and the slope of the road isless than the fourth slope threshold (p4), and the current speed isgreater than the first speed threshold, the engine is started. Afterstarting the engine, it may be further determined whether the currentspeed of the hybrid electric vehicle is less than a second speedthreshold, if yes, the engine is configured to stop and the motor isconfigured to output power separately, and if no, step S601 is returnedto, for performing the engine start-stop control procedure again.

In step S607, the slope of the road on which the hybrid electric vehicleis driving obtained, and step S608 and S609 are performed.

In step S608, it is determined whether the road is ascent and the slopeof the slope of the road is less than a first slope threshold (p1), ifyes, step S610 is performed, and if no, step S605 is performed.

In step S609, it is determined whether the road is descent and the slopeof the road is less than a second slope threshold (p2), if yes, stepS611 is performed, and if no, step S610 is performed.

In step S610, the current speed of the hybrid electric vehicle isobtained.

In step S611, the engine is configured to stop, and the motor isconfigured to output power separately.

In step S612, if the current speed is less than a third speed threshold,the engine is configured to stop, and the motor is configured to outputpower separately.

In step S613, if the current speed is greater than or equal to a thirdspeed threshold, and less than a fourth speed threshold, the hybridelectric vehicle is configured to enter the small load stop mode.

Specifically, it is first determined whether the engine is in anoperating state. If the engine is not in the operating state, it isfurther determined whether an accelerator push depth (d) is greater thanor equal to a first accelerator threshold (n). If the accelerator pushdepth is greater than or equal to the first accelerator threshold (n),the engine is started; and if the accelerator push depth is less thanthe first accelerator threshold (n), the state of the engine remainsunchanged.

If the engine is in the operating state, it is further determinedwhether the accelerator push depth is less than a second acceleratorthreshold (m). If the accelerator push depth is less than the secondaccelerator threshold (m), the engine is configured to stop; and if theaccelerator push depth is greater than or equal to the secondaccelerator threshold (m), the state of the engine remains unchanged.

The first accelerator threshold and the second accelerator threshold maybe set according to a driving habit of a user and a performance of thehybrid electric vehicle.

In step S614, if the current speed is greater than or equal to thefourth speed threshold, and less than a fifth speed threshold, thehybrid electric vehicle is configured to enter the small load stallmode.

Specifically, it is first determined whether the engine is in anoperating state. If the engine is not in the operating state, it isfurther determined whether an accelerator push depth (d) is greater thanor equal to a first accelerator threshold (n). If the accelerator pushdepth is greater than or equal to the first accelerator threshold (n),the engine is started; and if the accelerator push depth is less thanthe first accelerator threshold (n), the state of the engine remainsunchanged.

If the engine is in the operating state, it is further determinedwhether the accelerator push depth is less than a second acceleratorthreshold (m). If the accelerator push depth is less than the secondaccelerator threshold (m), the engine is configured to stall, the clutchremains in a coupling state, and fuel supply for the engine is cut off;and if the accelerator push depth is greater than or equal to the secondaccelerator threshold (m), the state of the engine remains unchanged.

The first accelerator threshold and the second accelerator threshold maybe set according to a driving habit of a user and a performance of thehybrid electric vehicle. The second accelerator threshold is less thanthe first accelerator threshold, thus avoiding a frequent enginestart-stop caused by unclear accelerator thresholds.

In step S615, if the current speed is greater than the fifth speedthreshold, the state of the engine remains unchanged.

In the above-described process, when causing the engine, the motor is inthe operating state, such that the motor may provide power for thevehicle separately or provide power for the vehicle along with theengine, according to different working states of the engine.

In some embodiments of the present disclosure, when the slope of theroad meets the preset condition, the hybrid electric vehicle isconfigured to enter the small load stop mode or the small load stallmode according to the slope of the road. If the slope of the roaddoesn't satisfy the preset condition, for example, if the road is ascentand the slope of the road is greater than or equal to the first slopethreshold, then it is executed to quit engine start-stop control, thehybrid electric vehicle is configured by the engine controller of thehybrid electric vehicle; and if the road is descent and the slope of theroad is less than the second slope threshold, the engine is configuredto stop, and the motor is configured to output power separately.

With the drive control method of the hybrid electric vehicle accordingto embodiments of the present disclosure, when the current gear positionof the hybrid electric vehicle and the current electric charge level ofthe power battery meet a preset requirement, the hybrid electric vehicleis configured to enter a small load stop mode or a small load stall modeaccording to the slope of the road on which the hybrid electric vehicleis driving. In this way, a driving distance for the vehicle may beincreased, an economy performance may be improved, and fuel consumptionand emission may be reduced, without increasing a working frequency ofthe starter, thus ensuring a working life of components. In addition, ifthe vehicle has an accelerator-releasing energy feedback function,wasted kinetic energy may be converted to electric energy by a motorthrough the energy feedback and stored in a power battery, thusincreasing energy recovery. Moreover, for the hybrid electric vehicles,problems of bad ride comfort and bad power performance caused byfrequent start-stop of the engine may be solved effectively.

A drive control device of a hybrid electric vehicle is also provided inthe present disclosure.

FIG. 7 is a block diagram of a drive control device of a hybrid electricvehicle according to an embodiment of the present disclosure.

As shown in FIG. 7, the drive control device according to an embodimentof the present disclosure includes a first obtaining module 10, a secondobtaining module 20 and a first control module 30.

Specifically, the first obtaining module 10 is configured to obtain acurrent gear position of the hybrid electric vehicle and a currentelectric charge level of a power battery.

The second obtaining module 20 is configured to obtain a slope of a roadon which the hybrid electric vehicle is driving, if the current gearposition of the hybrid electric vehicle and the current electric chargelevel of the power battery meet a preset requirement.

The first control module 30 is configured to control a working state ofan engine and/or a motor of the hybrid electric vehicle according to theslope of the road on which the hybrid electric vehicle is driving.

Specifically, in some embodiments according to the present disclosure,the first control module is configured to determine whether the slope ofthe road satisfies a preset condition, if the current gear position andthe current electric charge level of a power battery meet the presetrequirement. If the slope of the road satisfies the preset condition,the first control module is further configured to obtain a current speedof the hybrid electric vehicle and control the hybrid electric vehicleto enter a small load stop mode or a small load stall mode according tothe current speed. The specific causing process may be shown in FIG. 3.

Specifically, if the road is ascent and the slope of the road is lessthan the first slope threshold, then it is determined that the slope ofthe road satisfies the preset condition, or if the road is descent andthe slope of the road is greater than or equal to the second slopethreshold, then it is determined that the slope of the road satisfiesthe preset condition.

When it is determined that the slope of the road doesn't satisfy thepreset condition, the first control module is further configured to:

release the engine from start-stop control if the road is ascent and theslope of the road is greater than or equal to the first slope threshold,the hybrid electric vehicle may be configured by the engine controller;and

stop the engine and control a motor to output power separately if theroad is descent and the slope of the road is less than the second slopethreshold.

In some embodiments, as shown in FIG. 8 the drive control device furtherincludes a first determining module 40 and a third obtaining module 50.

The third obtaining module 50 is configured to obtain a currentoperating mode of the hybrid electric vehicle and a discharge power ofthe power battery.

The first determining module 40 is configured to determine whether thehybrid electric vehicle is within a taxiing start-stop intervalaccording to the current gear position and the current operating mode ofthe hybrid electric vehicle, the current electric charge level and thedischarge power of the power battery.

Specifically, as shown in FIG. 8, the first determining module furtherincludes: a first determining unit 41, a second determining unit 42 anda third determining unit 43.

The first determining unit 41 is configured to, if the current gearposition is at D-position and the current operating mode is at a hybrideconomy mode, determines whether the current electric charge level ofthe power battery is greater than a first electric charge levelthreshold, and whether the discharge power of the power battery isgreater than a first power threshold.

The second determining unit 42 is configured to, if the current electriccharge level of the power battery is greater than the first electriccharge level threshold, and the discharge power of the power battery isgreater than the first power threshold, determine whether the currentelectric charge level is greater than or equal to a second electriccharge level threshold, and whether a difference between the currentelectric charge level and a target electric charge level of the powerbattery is less than or equal to a preset value.

The third determining unit 43 is configured to, if the current electriccharge level is greater than or equal to the second electric chargelevel threshold, and the difference between the current electric chargelevel and the target electric charge level of the power battery is lessthan or equal to the preset value, determine that the hybrid electricvehicle is within the taxiing start-stop interval.

Alternatively, the first determining module may further include a fourthdetermining unit 44 configured to, if the current electric charge levelof the power battery is less than the second electric charge levelthreshold, or the difference between the current electric charge leveland the target electric charge level of the power battery is greaterthan the preset value, determine the hybrid electric vehicle is withinthe speed start-stop interval.

In some embodiments according to the present disclosure, as shown inFIG. 9, the drive control device further includes a second controlmodule 60.

The second control module is configured to, after it is determined thatthe hybrid electric vehicle is within a speed start-stop interval: startthe engine if the road is ascent and the slope of the road is greaterthan or equal to a third slope threshold; stop the engine and controlthe motor to output power separately if the road is descent and theslope of the road is greater than or equal to a fourth slope threshold;and start the engine if the is ascent and the slope of the road is lessthan the third slope threshold and the current speed is greater than afirst speed threshold, or if the road is descent and the slope of theroad is greater than or equal to a fourth slope threshold and thecurrent speed is greater than a first speed threshold.

After the engine is started, the second control module is furtherconfigured to obtain a current speed of the hybrid electric vehicleafter the engine is started; determine whether the current speed is lessthan a second speed threshold; stop the engine and control the motor tooutput power separately if the current speed is less than a second speedthreshold; and repeat obtaining a current speed of the hybrid electricvehicle if the current speed is great than or equal to a second speedthreshold.

With respect to the devices in the above embodiments, the specificoperation modes of individual modules therein have been described indetail in the embodiments regarding the drive control method of thehybrid electric vehicle, which will not be elaborated herein.

The energy transfer in a drive control process of a hybrid electricvehicle according to an embodiment of the present disclosure may beshown in FIG. 4, and the information interaction in a drive controlprocess of a hybrid electric vehicle according to an embodiment of thepresent disclosure may be shown in FIG. 5

With the drive control device of the hybrid electric vehicle accordingto embodiments of the present disclosure, when the current gear positionof the hybrid electric vehicle and the current electric charge level ofthe power battery meet a preset requirement, the hybrid electric vehicleis configured to enter a small load stop mode or a small load stall modeaccording to the slope of the road on which the hybrid electric vehicleis driving. In this way, a driving distance for the vehicle may beincreased, an economy performance may be improved, and fuel consumptionand emission may be reduced, without increasing a working frequency ofthe starter, thus ensuring a working life of components. In addition, ifthe vehicle has an accelerator-releasing energy feedback function,wasted kinetic energy may be converted to electric energy by a motorthrough the energy feedback and stored in a power battery, thusincreasing energy recovery. Moreover, for the hybrid electric vehicles,problems of bad ride comfort and bad power performance caused byfrequent start-stop of the engine may be solved effectively.

In some embodiments, a hybrid electric vehicle is also provided in thepresent disclosure. The hybrid electric vehicle includes the drivecontrol device described in any of above embodiments.

With the hybrid electric vehicle according to embodiments of the presentdisclosure, when the current gear position of the hybrid electricvehicle and the current electric charge level of the power battery meeta preset requirement, the hybrid electric vehicle is configured to entera small load stop mode or a small load stall mode according to the slopeof the road on which the hybrid electric vehicle is driving. In thisway, a driving distance for the vehicle may be increased, an economyperformance may be improved, and fuel consumption and emission may bereduced, without increasing a working frequency of the starter, thusensuring a working life of components. In addition, if the vehicle hasan accelerator-releasing energy feedback function, wasted kinetic energymay be converted to electric energy by a motor through the energyfeedback and stored in a power battery, thus increasing energy recovery.Moreover, for the hybrid electric vehicles, problems of bad ride comfortand bad power performance caused by frequent start-stop of the enginemay be solved effectively.

In the specification, it is to be understood that terms such as“central,” “longitudinal,” “lateral,” “length,” “width,” “thickness,”“upper,” “lower,” “front,” “rear,” “left,” “right,” “vertical,”“horizontal,” “top,” “bottom,” “inner,” “outer,” “clockwise,” and“counterclockwise” should be construed to refer to the orientation asthen described or as shown in the drawings under discussion. Theserelative terms are for convenience of description and do not requirethat the present invention be constructed or operated in a particularorientation.

In addition, terms such as “first” and “second” are used herein forpurposes of description and are not intended to indicate or implyrelative importance or significance or to imply the number of indicatedtechnical features. Thus, the feature defined with “first” and “second”may comprise one or more of this feature.

In the present disclosure, unless specified or limited otherwise, theterms “mounted,” “connected,” “coupled,” “fixed” and the like are usedbroadly, and may be, for example, fixed connections, detachableconnections, or integral connections; may also be mechanical orelectrical connections; may also be direct connections or indirectconnections via intervening structures; may also be inner communicationsof two elements, which can be understood by those skilled in the artaccording to specific situations.

In the present disclosure, unless specified or limited otherwise, astructure in which a first feature is “on” or “below” a second featuremay include an embodiment in which the first feature is in directcontact with the second feature, and may also include an embodiment inwhich the first feature and the second feature are not in direct contactwith each other, but are contacted via an additional feature formedtherebetween. Furthermore, a first feature “on,” “above,” or “on top of”a second feature may include an embodiment in which the first feature isright or obliquely “on,” “above,” or “on top of” the second feature, orjust means that the first feature is at a height higher than that of thesecond feature; while a first feature “below,” “under,” or “on bottomof” a second feature may include an embodiment in which the firstfeature is right or obliquely “below,” “under,” or “on bottom of” thesecond feature, or just means that the first feature is at a heightlower than that of the second feature.

Reference throughout this specification to “an embodiment,” “someembodiments,” “one embodiment”, “another example,” “an example,” “aspecific example,” or “some examples,” means that a particular feature,structure, material, or characteristic described in connection with theembodiment or example is included in at least one embodiment or exampleof the present disclosure. Thus, the appearances of the phrases such as“in some embodiments,” “in one embodiment”, “in an embodiment”, “inanother example,” “in an example,” “in a specific example,” or “in someexamples,” in various places throughout this specification are notnecessarily referring to the same embodiment or example of the presentdisclosure. Furthermore, the particular features, structures, materials,or characteristics may be combined in any suitable manner in one or moreembodiments or examples.

Although explanatory embodiments have been shown and described, it wouldbe appreciated by those skilled in the art that the above embodimentscannot be construed to limit the present disclosure, and changes,alternatives, and modifications can be made in the embodiments withoutdeparting from spirit, principles and scope of the present disclosure.

What is claimed is:
 1. A drive control method of a hybrid electricvehicle, comprising: obtaining a current gear position of the hybridelectric vehicle and a current electric charge level of a power battery;obtaining a slope of a road on which the hybrid electric vehicle isdriving, if the current gear position of the hybrid electric vehicle andthe current electric charge level of the power battery meet a presetrequirement; and controlling a working state of an engine and/or a motorof the hybrid electric vehicle according to the slope of the road onwhich the hybrid electric vehicle is driving.
 2. The drive controlmethod according to claim 1, wherein the preset requirement comprises:the current gear position is at D-position, and the current electriccharge level of the power battery is greater than a first electriccharge level threshold.
 3. The drive control method according to claim1, further comprising: obtaining a current operating mode of the hybridelectric vehicle and a discharge power of the power battery; anddetermining whether the hybrid electric vehicle is within a taxiingstart-stop interval according to the current gear position and thecurrent operating mode of the hybrid electric vehicle, the currentelectric charge level and the discharge power of the power battery. 4.The drive control method according to claim 3, wherein determiningwhether the hybrid electric vehicle is within the taxiing start-stopinterval according to the current gear position and the currentoperating mode of the hybrid electric vehicle, the current electriccharge level and the discharge power of the power battery comprises: ifthe current gear position is at D-position and the current operatingmode is at a hybrid economy mode, further determining whether thecurrent electric charge level of the power battery is greater than afirst electric charge level threshold, and whether the discharge powerof the power battery is greater than a first power threshold; if thecurrent electric charge level of the power battery is greater than thefirst electric charge level threshold, and the discharge power of thepower battery is greater than the first power threshold, furtherdetermining whether the current electric charge level is greater than orequal to a second electric charge level threshold, and whether adifference between the current electric charge level and a targetelectric charge level of the power battery is less than or equal to apreset value; if the current electric charge level is greater than orequal to the second electric charge level threshold, and the differencebetween the current electric charge level and the target electric chargelevel of the power battery is less than or equal to the preset value,determining that the hybrid electric vehicle is within the taxiingstart-stop interval.
 5. The drive control method according to claim 4,wherein if it is determined that the hybrid electric vehicle is withinthe taxiing start-stop interval, controlling the working state of theengine and/or the motor of the hybrid electric vehicle according to theslope of the road on which the hybrid electric vehicle is drivingcomprises: determining whether the slope of the road satisfies a presetcondition; obtaining a current speed of the hybrid electric vehicle ifthe slope of the road satisfies the preset condition; and causing thehybrid electric vehicle to enter a small load stop mode or a small loadstall mode according to the current speed.
 6. The drive control methodaccording to claim 5, wherein the preset condition comprises: the slopeof the road is less than a first slope threshold if the road is ascent,or the slope of the road is greater than or equal to a second slopethreshold if the road is descent.
 7. The drive control method accordingto claim 4, further comprising: determining the hybrid electric vehicleis within a speed start-stop interval if the current electric chargelevel is less than the second electric charge level threshold, or if thedifference between the current electric charge level and the targetelectric charge level of the power battery is greater than the presetvalue.
 8. The drive control method according to claim 5, wherein causingthe hybrid electric vehicle to enter a small load stop mode or a smallload stall mode according to the current speed comprises: if the currentspeed is less than a third speed threshold, stopping the engine, andcausing a motor to output power separately; if the current speed isgreater than or equal to the third speed threshold, and less than afourth speed threshold, causing the hybrid electric vehicle to enter thesmall load stop mode; if the current speed is greater than or equal tothe fourth speed threshold, and less than a fifth speed threshold,causing the hybrid electric vehicle to enter the small load stall mode;and if the current speed is greater than the fifth speed threshold,keeping a state of the engine unchanged.
 9. The drive control methodaccording to claim 5, wherein causing the hybrid electric vehicle toenter the small load stop mode comprises: determining whether the engineis in an operating state; if the engine is not in the operating state,further determining whether an accelerator push depth is greater than orequal to a first accelerator threshold; if the accelerator push depth isgreater than or equal to the first accelerator threshold, starting theengine; and if the accelerator push depth is less than the firstaccelerator threshold, keeping a state of the engine unchanged.
 10. Thedrive control method according to claim 5, wherein causing the hybridelectric vehicle to enter the small load stall mode comprises:determining whether the engine is in an operating state; if the engineis not in the operating state, further determining whether anaccelerator push depth is greater than or equal to a first acceleratorthreshold; if the accelerator push depth is greater than or equal to thefirst accelerator threshold, starting the engine; and if the acceleratorpush depth is less than the first accelerator threshold, keeping a stateof the engine unchanged.
 11. A drive control device of a hybrid electricvehicle, comprising: a first obtaining module, configured to obtain acurrent gear position of the hybrid electric vehicle and a currentelectric charge level of a power battery; a second obtaining module,configured to obtain a slope of a road on which the hybrid electricvehicle is driving, if the current gear position of the hybrid electricvehicle and the current electric charge level of the power battery meeta preset requirement; and a first control module, configured to controla working state of an engine and/or a motor of the hybrid electricvehicle according to the slope of the road on which the hybrid electricvehicle is driving.
 12. The drive control device according to claim 11,wherein the preset requirement comprises: the current gear position isat D-position, and the current electric charge level of the powerbattery is greater than a first electric charge level threshold.
 13. Thedrive control device according to claim 11, further comprising: a thirdobtaining module, configured to obtain a current operating mode of thehybrid electric vehicle and a discharge power of the power battery; anda first determining module, configured to determine whether the hybridelectric vehicle is within a taxiing start-stop interval according tothe current gear position and the current operating mode of the hybridelectric vehicle, and the current electric charge level and thedischarge power of the power battery.
 14. The drive control deviceaccording to claim 13, wherein the first determining module comprises: afirst determining unit, configured to, if the current gear position isat D-position and the current operating mode is at a hybrid economymode, determine whether the current electric charge level of the powerbattery is greater than a first electric charge level threshold, andwhether the discharge power of the power battery is greater than a firstpower threshold; a second determining unit, configured to, if thecurrent electric charge level of the power battery is greater than thefirst electric charge level threshold, and the discharge power of thepower battery is greater than the first power threshold, determinewhether the current electric charge level is greater than or equal to asecond electric charge level threshold, and whether a difference betweenthe current electric charge level and a target electric charge level ofthe power battery is less than or equal to a preset value; and a thirddetermining unit, configured to, if the current electric charge level isgreater than or equal to the second electric charge level threshold, andthe difference between the current electric charge level and the targetelectric charge level of the power battery is less than or equal to thepreset value, determine that the hybrid electric vehicle is within thetaxiing start-stop interval.
 15. The drive control device according toclaim 14, wherein if it is determined that the hybrid electric vehicleis within the taxiing start-stop interval, the first control module isconfigured to: determine whether the slope of the road satisfies apreset condition; obtain a current speed of the hybrid electric vehicleif the slope of the road satisfies the preset condition; and control thehybrid electric vehicle to enter a small load stop mode or a small loadstall mode according to the current speed.
 16. The drive control deviceaccording to claim 15, wherein the preset condition comprises: the slopeof the road is less than a first slope threshold if the road is ascent,or the slope of the road is greater than or equal to a second slopethreshold if the road is descent.
 17. The drive control device accordingto claim 16, wherein the first control module is further configured to:release the engine from start-stop control if the road is ascent and theslope of the road is greater than or equal to the first slope threshold;and stop the engine and control a motor to output power separately ifthe road is descent and the slope of the road is less than the secondslope threshold.
 18. The drive control device according to claim 14,wherein the third determining unit is further configured to determinethe hybrid electric vehicle is within a speed start-stop interval if thecurrent electric charge level is less than the second electric chargelevel threshold, or if the difference between the current electriccharge level and the target electric charge level of the power batteryis greater than the preset value.
 19. The drive control device accordingto claim 15, wherein the first control module is configured to: stop theengine, and control a motor to output power separately, if the currentspeed is less than a third speed threshold; control the hybrid electricvehicle to enter the small load stop mode, if the current speed isgreater than or equal to the third speed threshold, and less than afourth speed threshold; control the hybrid electric vehicle to enter thesmall load stall mode, if the current speed is greater than or equal tothe fourth speed threshold, and less than a fifth speed threshold; andremain a state of the engine unchanged, if the current speed is greaterthan the fifth speed threshold.
 20. A hybrid electric vehicle,comprising the drive control device according to claim 11.